#!/usr/bin/env python3
# ------------------------------------------------------------
# Programmer(s):  Daniel R. Reynolds @ SMU
# ------------------------------------------------------------
# SUNDIALS Copyright Start
# Copyright (c) 2002-2025, Lawrence Livermore National Security
# and Southern Methodist University.
# All rights reserved.
#
# See the top-level LICENSE and NOTICE files for details.
#
# SPDX-License-Identifier: BSD-3-Clause
# SUNDIALS Copyright End
# ------------------------------------------------------------
# matplotlib-based plotting script for brusselator1D.c example

# imports
import sys
import pylab as plt
import numpy as np

# load mesh data file
mesh = np.loadtxt("bruss_FEM_mesh.txt", dtype=np.double)

# load solution data files
udata = np.loadtxt("bruss_FEM_u.txt", dtype=np.double)
vdata = np.loadtxt("bruss_FEM_v.txt", dtype=np.double)
wdata = np.loadtxt("bruss_FEM_w.txt", dtype=np.double)

# determine number of time steps, mesh size
nt, nx = np.shape(udata)

# determine min/max values
umin = 0.9 * udata.min()
umax = 1.1 * udata.max()
vmin = 0.9 * vdata.min()
vmax = 1.1 * vdata.max()
wmin = 0.9 * wdata.min()
wmax = 1.1 * wdata.max()
minval = np.array([umin, vmin, wmin]).min()
maxval = np.array([umax, vmax, wmax]).max()

# plot the mesh
plt.figure(1)
plt.plot(mesh, 0.0 * mesh, "o")
plt.xlabel("x")
plt.title("FEM mesh")
plt.savefig("brusselator1D_FEM_mesh.png")

# generate plots of results
for tstep in range(nt):

    # set string constants for output plots, current time, mesh size
    pname = "brusselator1D_FEM." + repr(tstep).zfill(3) + ".png"
    tstr = repr(tstep)
    nxstr = repr(nx)

    # plot current solution and save to disk
    plt.figure(1)
    plt.plot(mesh, udata[tstep, :], label="u")
    plt.plot(mesh, vdata[tstep, :], label="v")
    plt.plot(mesh, wdata[tstep, :], label="w")
    plt.xlabel("x")
    plt.ylabel("solution")
    plt.title("Solutions at output " + tstr + ", mesh = " + nxstr)
    plt.axis((0.0, 1.0, minval, maxval))
    plt.grid()
    plt.legend(loc="upper right", shadow=True)
    plt.savefig(pname)
    plt.close()


##### end of script #####
